Sound record and method of making the same



E. E. NOVOTNY SOUND RECORD AND METHOD 0F MAKING THE SAME plri 8, 1924.

Filed Jam. 5,

Patented Apr, 8, 1924.

untreu srv-Aras 1,489,669 PATENT OFFICE.

EMIL E. NOVQTNY, OF LOG-AN, PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T' JOHN STOGDmfL STORES, 0F AHUN'IINGDON VALLEY POST OFFICE, PENNSYLVANIA.

SOUND RECORD AND METHOD 0F MAKING THE SAMIE.

Application led January 3, 1922. Serial No. 526,860.

In the present instance it is my purpose to make the matrices of such material, and by such methods, that a great saving 1n time,

' labor and expense is attained inasmuch as I do not only eliminate several of the tedious steps usually followed. in forming those matrices which are ordinarily used in Vmolding or reproducing commercial sound records, but I make such matrices of an easily obtainable, readily moldable material, such as lead, or analloy thereof. l

As is well known, in the practice of making sound record matrices, heretofore followed, it has been usual to apply to the original Wax master record a chemically produced film of silver in order to obtain the necessary surface conductivity, a master matrix being then formed by electro-deposition against this silver film. This operation of forming the master matrix by electrodeposition requires from 24 to 48 hours, after which the now formed master matrix, or punch, is stripped from the wax surface of the original master record and is cleaned and polished. YThis master matrix is then coated with a separating film of some oxidizing agent, such as aweak solution of iodine or pyrogallic acid, and this master matrix is then used for making a metallic master record, which is also formed by electro-deposition, consuming the same length of time in its formation as was required for the master matrix-from 24 to 48 hours. This metallic master record is in turn used for making a large number of, sub-master matrlces or punches, these duplicate matrlces i being also kformed by the slow process of electro-de osition against the metallic master record, and when 4completed such sub-master matrices are employed for the molding of the commercial run of sound records:

In practicing my invention, while I pro duce the master matrix from the original wax record, and also produce the metallic master record by electro-deposition as is the ordinary practice, I thereafter dispense with the practice of the slow and expensive"k process of electro-deposition in the formation of the numerous duplicate sub-master matrices or punches intended to be used in molding the commercial sound record, and instead, I take the metallic master record and bring it into contact with a sheet, or body, of a soft, readily fusible metal, such as lead, or an alloy of lead, and while the metallic sheet, or body, is in a molten, or partially molten. plastic pasty, yet nont'ree-lowing' condition, I subject the assembled master record and the matrix-forming material to relatively light pressure, to form the molding face of the sound record matrix, at the same time cooling the assembled elements to harden the matrix body, after which the press may be opened, and the master record stripped from the now completed matrix, and which latter may be used in the formation or molding of commercial sound records. This operation of pressing or molding the sound record matrix directly from the metallic master record can be accomplished in from 2 to 5 minutes, which is ,a great saving in time and expense over the old electro-deposition process above mentioned. The result is that a great many metallic matrices can be quickly made from the same metallic record, as the latter will be available for use in making a new matrix every few minutes, and this is a distinct advantage whereit is desirable to have a. largel number of matrices for molding commercial sound records bearing the same selection, such for example as a popular musical composition.

My invention consists in the sound record matrix, and inthe method of making the same set forth in and' falling within the scope of the appended claims.

In the accompanying drawings:

Figure 1 is a view in end elevation of a slab of metal, such as a low-melting alloy, which may be used in the making of my matrix;

Figure 2 is a cross sectional View of the slab-receiving pan;

Fi re 3 is a View in cross section of a. metalic master recordmounted on a vhaag of my sound record matrix;

Figure 4 is a view showing conventionally the platens of a press and illustratlng the manner of forming the matrix by placing the metallic master record against the molten or partially-molten metal and subjecting the same to pressure and coolmg by the action of air;

Figure 5 is a view illustrating conventionally another arrangement of a press and showing the manner of making the matrix by subjecting the metallic master record to mechanical pressure while in contact with a pasty, mushy or partially-melted body of metal;

Figures 6, 7 and 8 are cross sectional views illustrating forms of matrices which may be made by the practice of my invention.

I will first describe the manner of making a matrix by placing the mounted metallic master record in a molten bath of metal and subjecting the same to pressure and cooling and hardening under the action of air, and in this connection will refer to Figures 1 to 4 inclusive.

I select a suitable metal having the desired melting point and the ability to assume a pasty, mushy or plastic condition before setting to its final hard form, my preference being an alloy consisting of six parts 0f lead, six parts 'of tin and one part of bismuth, by wei ht. Such an alloy has a melting point of av out 327 degrees F. This metallic alloy, which may be in the form of a slab such as is shown in Figure 1, is melted down in a suitable container, and when the matrix is to be made such molten metal may be run or poured into the pan 2 shown in Figure 2. The pan is preferably provided with a ring 3, the vertical wall of which forms an overflow rim 4, so that when the mounted master record is placed in contact with the molten metal the surplus metal displaced will flow over the edge of the ring and into the gutter 5. As will be seen by reference to Figure 3, the master record R is centered on the diemember base 6 by means of a center pin 7, and is securely held by the clamping ring S screwed to the base as at 8. This clamping ring 8 is formed with a sharp annular shoulder 10 for the purpose of producing the circular form which is preferable in a matrix, and the center pin 7 projects beyond the metallic master record in order to form a hole in the center of the matrix being made, and which hole will later serve in positioning the matrix 011 a spindle or label-holding device, in molding'sound records, as is well known.

In making the matrix in one preferred way, I use a press P, Figure 4. The press includes a top platen 9 and a lower platen 9'. The lower platen is provided with a chamber or channel l1 for the passage of a heating agent, such as steam, and the top platen may be similarly provided with a p cold air under pressure to chamber 17.V

There is also an outlet such as pipe 13 for the escape of heat or waste air from the chamber, and a vacuum outlet 14 may also be supplied when it is desired to reduce the amount of air in the chamber. The air inlet 12 is preferably provided with a pulsating valve 19, while the air outlet 18 is provided with a bleed valve 20, and the exhaust outlet 14 is provided with a suitable valve such as a globe valve 21, these valves being merely conventionally indicated. The lower platen may be provided with avvalved steam inlet pipe 22 and a steam exhaust pipe 23.

In making the matrix the master record R is first treated with a separating medium. If desired it may be provided with a very thin electrolytic Iilm, produced by treating it in a shallow electrolytic bath. This coating is shown at 24. The form thus coated is then treated to another coating of an oxidizingl agent, such as a weak solution of iodine or pyrogallic acid, and is then treated to a third coating or surface coating of graphite, although this latter is not essential, but the graphite will assist in the ready separation of the master record from the matrix while the electrolytic and iodine coating will prevent the amalgamation of the molten metal with the master record.

A slab 1 of the alloy, having been melted down and run into a pan, the latter is placed upon the bottom platen of the press as shown in Figure 4, such platen being heated at this time by the passage of steam therethrough, thus keeping the alloy in a fluidlike or molten condition until the press is closed and the matrix-making operation is in progress. Before placing the pan of the molten metal in the press, I preferably place upon the surface of the metal an oily substance, such as parafiine, which prevents the formation of oxide upon the surface of the bath and assists in the subsequent separation of the master record from the hardened matrix. The master record R is now inverted or placed face down in the molten bath, the depth of immersion being limited by the clamping ring which projects through the molten mass and rests upon the bottom of the pan. 'This ring is of such type, however, as to permit the entire face of the master record to be immersed in the bath to the desired depth. The press is now closed to form an airtight chamber. The heating steam is now Cut Gif, and. ythe vacuum valve being closed because the vacuum 1s notused 1n this 1nstance, the outlet valve of the air outlet 1.3 is opened and air under pressure is forced in waves or pulsations through the chamber will drive the warmair outl p through the pipe 13, and such cool air, at the same time, coming 1n pulsations as 1t does will not only cool and 'set the'body of metal, first to a pasty, mushy or plastlc condition and then to its final or hard condition, but will punch or compact the graduallycooling or solidifying metal up against and into intimate contact with every portion of thc area of the master record face. This pulsation admission of the air may be continued for a suitable period, say for about two minutes, at the end of which time the metal will be suiiiciently solidified or hardened as tohave assumed a rigid condition, and the matrix will have been produced with the greatest detail with relation to the face of the master record. The air may now be cut off from the air Ainlet 12 and the press ,opened and theepan with the now solidified matrix and master record may be lifted out and the master record removed. This separation is easily accomplished owing to the layer of parafiin which has been placed upon the metal and the coatings on the face of the master record. The metal matrix will not stick to thepau because the latter is made of ordinary steel which has no affinity for an alloy of the character I use.- The sound grooves of the master record will be faithfully reproduced as elevated ribs on the matrix, thus forming the molding face of the latter.

In some instances, instead of first melting down the alloy slab and running it in molten form into the pan, I may place the slab in the pan, apply the paraflin to the face of the slab, and thenl place the inverted masterA record on the slab and close the press. case will be accomplished by the steam passing through the lower platen of the press, but before so melting down the slab, or while the press .is closed, the exhaust valve 21 of the vacuum outlet 14 may be opened and vacuum applied to draw from the closed chamber as much air as possible. The melting down of the slab may now take place, thevacuum closed or cut. olf. and the admission ofcold air pressure and the exhaustion of thehot air accomplished as heretofore described to formi the mgatrix, after! the master record has imbedded itself by gravity into the fused or melted slab.

In Figure 5 I have shown a modified ar rangement for making the matrix,

The melting down of the slab in this.I

In this case'the numeral 30 indicates the lower, vertically-movable platen cf the press, while 31 is an upper, stationary platen, preferably provided with a steam inlet 32, and a steam outlet 33, so that the platen may be heated if desired. This upper plate-n carries at one side a master record clamping ring section 34 which is stationary, and at the opposite side a movable or shifting clamping ring section 35, the latter being shiftable in any well known manner as by means of the rotatable screw 36, upon which travels the threaded sleeve 37 carrying the clamping ring section 35, a suitable hand-wheel v38 being provided for rotating the screw. The master record R which may or may not have its face coated with the separating medium as afore described, is clamped between the clamping ring section, as shown, and is therefore held suspended vat the under side of the upper platen of the press. Upon the lower platen of the press isplaced a base-board 38 of asbestos or -other nonconducting material, and upon this baseboard rests a shallow pan 39, in which has been placed a bath of molten metal, the surface of the bath having had the paraiiin placed thereon as before mentioned. This lower, vertically-moving platen is provided with a side bearer bar 40 which is adapted to contact with the stationary clamping ring section 34 when the press is closed,

while the upper platen of thepress carries a bearer bar 41 adapted to contact with the lower platen of the press whenthe latter is closed. y

When the pan with the bath of molten metal is placed in the press, the latter is kept open until the metal has partially solidified or cooled, or has assumed a pasty, mushy, plastic condition. -At this stage the press may be closed and the matrix molded, in this instance, however, air pressure not being used, as the pressure exerted in making the matrix is lentirely mechanical and is accomplished by the vertical movement or closing action of the lower platen, which forces the plastic or pasty mass upward and into contact with the face of the master record, the depth of penetration being, of course, limited bythe side bearer bars. The press remains closed for about one half minute which is suflicient to permit the cooling and solidifying ofthe metal. Of course, during this cooling or solidifying ofthe metal, the steam has been cut off from the vupper platen, and if desired, cold air or walike or flowing condition, the molding may take place after the alloy has been heated sufficiently to reduce it to a pasty, mushy or plastic mass, but not to a fluid state.

In Figure 6 I have shown at M an allalloy sound record matrix made in the way heretofore described, while in Figure 7 I have shown at M a modified form of nia trix comprising a body section m of the alloy and a facing section m thereof formed of a layer of metallic foil, such as a foil composed of equal proportions of tin and lead, which has been rolled in or impressed upon the master record prior to the making of the matrix, and which has adhered to the matrix body during the molding operation.

In Figure 8 the modified form of sound record matrix shown at M2 is composed of an alloy body m2 having an electroplated coating m3 which was deposited upon the face of the metallic master record prior to the molding of the matrix, or which may be deposited upon the alloy matrix body after the matrix is formed.

Sound record matrices made in accordance with my invention may be produced with a very light, or a minimum amount of pressure, and when cooled and set such matrices are capable of withstanding rough usage, thereby enabling a large number of reproductions or commercial sound records to be economically made therefrom. These matrices are particularly well adapted for molding sound records made from such materials as synthethic resin, shellacs, asphaltum and similar plastic substances, capable of being hardened and set to form the final product.

While I have herein shown and described certain preferred embodiments of my invention, I wish it to be understood that I-do not confine myself to all the precise details herein set forth, as modification and variation may 'be made without departing from the spirit of the invention or exceeding the scope of the appended claims.

What I claim is:

1. rlhe herein described method of making a sound record matrix which comprises preparing a master record and then pressing the grooved face of the latter against a body of soft plastic metal, then cooling the body Lasacee of metal to harden and set the same while the master record is in pressing relation therewith, and then separating the master record from the resultant hardened matrix.

2. The herein described method of making a sound record matrix which comprises preparing a metallic master record, then pressing the grooved face of the latter against a body of soft plastic metal while employing a separating medium between the master record and the body of metal, cooling the body of metal to harden and set the same while the master record is assembled therewith, and then separating the master record from the resultanthardened matrix.

3. The herein described method of making a sound record matrix which comprises pressing a master record against a body of metal while the latter is in a plastic, pasty condition, and simultaneously applying cooling action to harden and set the matrix, and then separating the master reco'rd from the matrix.

4. The herein described method of making a sound record matrix which com rises applying a master record to a body o soft plastic metal and subjecting the same to air pressure and cooling to form the matrix, and then separating the master record and matrix.

5. The herein described method of making a sound record matrix which comprises applying a master record to a body of soft plastic metal and subjecting the same to simultaneous air pressure and cooling to form the matrix, and applying a face coating to the matrix.

6. A sound record matrix comprising a body of metallic alloy having a coating on one face thereof, said coated face having grooves and ribs impressed on one face thereof.

7. A sound record matrix comprising a body of lead alloy having a coating on one face thereof, said coated face having elevations and de ressions impressed thereon.

Signed at hiladelphia, in the county of Philadelphia and State of Pennsylvania, this 23rd day of December, A. D. 1921.

EMIL E. NOVOTNY. 

